Hot Secret! Scientists Find a Giant Heat Mystery Hidden Deep Inside Mars
Quick Summary
Scientists have discovered something surprising hiding deep inside Mars. The southern half of the planet’s interior is hundreds of degrees hotter than the northern half. The discovery was published in the science journal Nature and could give us big clues about Mars’s history — and whether it ever had life.
What Happened?
Researchers at Caltech and the University of Arizona had a question: Is the inside of Mars the same temperature everywhere? To find out, they used data from three spacecraft orbiting Mars. They measured tiny changes in the planet’s gravity — the invisible pull that holds everything on the surface.
Those gravity measurements acted like X-rays. They let scientists build a 3D map of Mars’s interior without ever drilling into the ground!
What they found was a big surprise. The southern half of Mars’s mantle — the thick rocky layer between the crust and the core — is about 200 to 400 degrees Celsius hotter than the northern half. In Fahrenheit, that is like the difference between a warm summer day and a blast furnace.
Some of that rock deep in the south may even be partially melted, like slow-moving lava trapped underground.
Why Does It Matter?
Mars looks very different from north to south, even on the surface. The south has tall mountains and cratered highlands. The north has flat, low plains. Scientists have long wondered why. This hidden heat difference deep inside the planet may explain it.
The heat could also explain something else strange. Years ago, NASA’s InSight lander found that earthquake-like rumbles on Mars lose energy faster when they travel through the southern part of the planet. A hotter, softer southern interior would explain that perfectly.
Old magnetic fingerprints locked in rocks in Mars’s southern hemisphere also hint that Mars once had a powerful magnetic field — like Earth does today. A hot southern interior could be responsible for creating that ancient field.
All of this is exciting because Mars’s magnetic field may have once protected a warmer, wetter planet — a planet that could have had conditions friendly to life. Scientists are still trying to figure out what caused the heat difference in the first place. One idea is that a giant space rock smashed into Mars’s northern side long ago, releasing heat from the north.
Big Words
- Mantle — the thick layer of rock that sits between a planet’s outer crust and its deep inner core; on Earth it flows very slowly, like super-thick syrup.
- Thermal anomaly — an unexpected hot or cold spot that scientists did not expect to find in a particular place.
- Gravity measurement — a way of measuring tiny changes in a planet’s gravitational pull to figure out what kinds of rock or material are hidden beneath the surface.
- Magnetic field — an invisible shield around a planet, created by moving liquid metal in its core; Earth’s magnetic field protects us from harmful solar radiation.
- Tidal tomography — a technique scientists use to “see” inside a planet by tracking how its gravity wobbles over time, similar to how doctors use sound waves to see inside the human body.
Fun Fact
Mars’s south pole region has mountains that are so tall, the tallest — Olympus Mons — is three times higher than Mount Everest. Scientists now think all that towering terrain in the south may be partly connected to the mysterious heat lurking underground!
Think About It
If Mars once had liquid water, a magnetic field, and warm temperatures underground, what would you need to look for to know if tiny life forms ever lived there?
Sources
- Caltech — Thermal Anomaly Discovered Below Mars’s South Pole
- Phys.org — Thermal anomaly discovered below Mars’ south pole
- ScienceDaily — Scientists Discover a Massive Heat Anomaly Deep Inside Mars
- 404 Media — Scientists Discover Vast Underground ‘Anomaly’ on Mars